


The Estrus Effect

by ALPHAwolf



Series: Thundercats, Hoe! [1]
Category: Thundercats (2011)
Genre: Angst, Canon Compliant, F/F, M/M, Mating Cycles/In Heat, Pre-Canon, Short, Smut, adoptive-sibling incest, animal mating habits, mentions of f/f
Language: English
Status: Completed
Published: 2020-01-13
Updated: 2020-01-13
Packaged: 2021-02-27 14:28:40
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,565
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22238638
Author URL: https://archiveofourown.org/users/ALPHAwolf/pseuds/ALPHAwolf
Summary: Not long before everything goes to shit an ‘incident’ occurs between Tygra and Lion-O.
Relationships: Lion-O/Tygra
Series: Thundercats, Hoe! [1]
Series URL: https://archiveofourown.org/series/1600777
Comments: 3
Kudos: 45





	The Estrus Effect

**Author's Note:**

> For this short series there is no homophobia on Third Earth because animals don't give a shit about same sex couples but same sex partners are not recognized legally as life-mated partners.  
> Another important note- Male big-cats don't go into ‘heat’ but smelling a female in estrus will make them super horny (irl)

A warm breeze brushed against Lion-O’s short mane, his eyes shut as the young prince breathed in the scent of the palace garden. It was always beautiful in the spring, every flower open and fragrant. His father had told him the garden was once the queen’s favourite place in the entire of Thundera, hundreds of rare and beautiful flora having been traded for and planted. In a way it made him feel closer to a mother he’d never known, spending time sitting up in the branches of the largest tree. It gave a wonderful view of the kingdom too, not to mention providing ample concealment when he was avoiding his studies.

His ear twitched at the sound of a bush rustling, interest piqued as a quiet giggle followed. Curious, he opened his eyes and looked about from his vantage point, sniffing at the wind for a trail.

A musky smell slowly wafted into his nose, easily distinguishable from the sweet floral scents around him. As if triggering some deep heathen instinct he felt his body tense up and gave in to the urge to hunt for the source.

Like an excited kit in a game of hide and seek he leapt from the tree and silently stalked through the garden, sniffing and listening closely.

His head shot towards another sound- a feminine moan- and he peeked through foliage towards a large hedge. The bush rustled softly.

“ _Ohhhh~_ ” Lion-O’s face must have radiated colour at the speed it heated up, realising he had stumbled upon what must have been a cleric and gardener in heated embrace, if the mask left on the grass and gardening tools where anything to go by.

Another moan came and the fragrance of their coupling hit him like it was being forced up his nose. He quickly turned and made his silent escape back through the garden and into the palace, as far from the two she-cat’s as possible.

He made a breath of relief as he finally managed to take in fresh air, filling his lungs and slowing his pace. Their moans no longer filled his ears and yet he couldn’t stop hearing it, even with the clash of weapons and boisterous laughter up ahead.

As usual the courtyard held a small mass of males, each testing their strength and skill against one another. Lion-O stopped only a moment when he spotted his brother among them, an involuntary sour expression crossing his face. He could never help the jealousy that rose up within him at Tygra’s presence. He was just so… cocky, with that smug smile that made him want to punch him in the face. Even worse was knowing the other was favoured for the crown, considered better than him in every way by those around them. Even his father preferred the tiger, much to his chagrin.

Tygra flicked his whip with expert precision, disappearing a moment before appearing behind his enemy, that sharp grin on his lips. The snap of it echoed through the halls, heat suddenly flooding Lion-O’s body as he tensed up.

His brother easily overpowered his opponent, forcing them to the ground as his muscles rippled, panting with the heat that no doubt affected him more than all the other’s due to his undercoat.

Lion-O’s mouth was suddenly dry, the blood in his body rushing south as he sucked in a shaky breath.

His member twitched, pressing against the folds of his privates as the muscles involuntarily swelled.

Eyes wide with horror he turned tail and scampered away, rushing to the privacy of his bedroom to freak out.

~~s~~

Still panting in an attempt to cool down from his sparring session and considering going down to the pond for a swim Tygra padded through the palace, his veins buzzing with the adrenaline of victory.

As he came to the T junction at the end of the hall, one which would take him up towards the royal chambers and the other down to the pool he couldn’t help but pause, a curious smell having caught his attention. It was faint, and oddly familiar, but he couldn’t quite place it, and he couldn’t seem to turn away. He found himself abandoning his thoughts of cool water and walking up the steps, his nose twitching as he followed the invisible trail.

It seemed to grow stronger with each step, his muscles tensing with the thrill of the hunt, leading him up towards… his brother’s chambers?

Snarf was pawing at the door of the prince’s bedroom, looking concerned _. Had Lion-O kicked him out of the room?_ That was weird, to say the least.

Snarf made his strange squeak at him and pawed at the door again, giving him a desperate look. Curious, Tygra knocked gently, waiting impatiently for a reply. None came, and he knocked harder again.

“Lion-O?”

“ _G-go away!_ ” The tiger’s brow furrowed. He sounded distressed; _had he been injured?_ Now worried he tried the handle, finding the door unlocked and pushing it open.

The smell hit him like a punch in the face, forced to cover his nose at how overwhelming the pheromones were. It wasn’t a bad smell perse, but the sheer capacity of it was just too much for the room. He quickly shut the door behind him, Snarf crying out in protest from the other side, and immediately went for the window, opening it wide before daring to uncover his nose or look over to assess his brother’s condition.

Lion-O was sprawled half naked on the bed, panting heavily and shivering as if gripped by a fever. Tygra swallowed and ignored his body’s automatic response to the display, coming to the other’s side and pressing his hand against his forehead. As expected, he was burning up, eyes slipping between half-open as shut.

He leant in desperate for the touch, a pathetic whine sounding in his throat.

“Are you okay?” Tygra questioned in an attempt to get a clue as to what was ailing the other.

“I-I don’t know!” He looked terrified, staring up at him in a silent beg for help. Tygra scrunched up his nose as another wave of the strange smell hit him, realising suddenly what it reminded him of. His gaze flicked down the other’s trembling body and sure enough he was straining against his pants, the sheets and pillows arranged around him in almost a kind of nest.

He quickly looked away, mumbling to himself.

“Must have gotten a real nose full of a she-cat in heat,” he sighed and rubbed his neck at the awkward embarrassment his poor little brother would no doubt have to face in order to get an antidote, but there was nothing else he could do. “Don’t worry, I’ll get Jaga, you’ll be fine.” He went to turn when the other suddenly grabbed his paw, sitting up and gripping it tightly.

“No!” He begged, tugging him back. “Please, don’t-don’t leave.” He whispered desperately, the vulnerable look he tried so hard to hide exposed like a fresh wound.

The tiger’s face softened with sympathy, recalling when he himself had first experienced the after-effects of smelling another in heat. It could spread like a disease in spring, but thankfully herbal remedies were effective and easy to come by. Still, the situation of acquiring them was always awkward, like going to pick up tampons or haemorrhoid cream. Personally, he wasn’t dying to repeat the experience, but Lion-O was too far gone to help himself and he couldn’t just leave and pretend he’d never seen anything. The other was burning up, and evidently far more susceptible to the effects than most if the way he was rubbing up against Tygra’s arm was anything to go by.

The older swallowed, his eyes wide as he watched his ‘sweet innocent baby brother’ nuzzle his fur, tongue darting out to drag up his arm.

_Whiskers_ , he’d been in there to long. The smell was _drowning_ him, and to make matters worse his own scent glands were beginning to throb- along with other areas. 

The lion made a weak sound, gazing up at him with vacant and hazed aqua eyes as he tugged him closer, his pupils so blown they were almost round.

Tygra tried to make words, to convince himself to stop letting the other _seduce_ him into bed, but he was so heady he couldn’t quite tell the difference between the other’s scent and his own. The room felt so much hotter than before, and yet he didn’t mind the heat as much as he had.

He dared to breath in, realising he had been holding his breath, and immediately regretted it. Even nip didn’t make his head spin like this.

Left feeling foggy and lax it was easy for Lion-O to pull him closer and nuzzle his face, their sensitive noses rubbing gently against one another.

Through the haze Lion-O was vaguely aware that he probably shouldn’t be doing this with his brother, what with them being related and all (even if it wasn’t by blood). Tygra was his rival, his opposite. Confident, egotistical, narcissistic, and yet now they were nuzzling like mates- and he never wanted to stop.

The tiger’s chest began to vibrate with a foreign sound, the deep noise almost like a growl or purr. He found himself melting into it, wondering if this was the legendary tiger’s churr as his brother began nuzzling and nipping at his sensitive ear.

The older was intoxicated by his little brother’s pheromones, the small coherent part of himself left yelling that Claudus would kill him if he took his precious baby’s virginity, but the thought faded as Lion-O made a moan, gripping his shoulders and luring him down into his nest.

Their lips brushed together as they descended, rough tongues meeting as they lapped at one another’s mouths, rubbing and nuzzling their faces against one another. He was vaguely aware of Lion-O tugging at his clothes before the other whined impatiently and began yanking. Tygra made a guttural sound as he sat up and helped tear his clothes off, some actual tearing taking place in their haste.

Lion-O’s underwear was removed too, small but distinct differences seen between their genitalia for a split second before their lower bodies met, both letting out twin moans. The sight of the other swelling played over behind Lion-O’s eyelids as they rubbed together, the other both longer and thicker than he. The colour was slightly different too, lighter and purpling at the tip, with the ridges of his spines far more prominent than his.

Lion-O hissed as they dragged against the sensitive skin of his member, still unable to help whimpering when the other pulled away and forced him to turn around. His body seemed to know what was going on better than he did, getting on all fours and spreading his thighs without prompt.

The sound Tygra made was a definite growl this time, the site of the smaller’s pink twitching pucker driving him mad with the desire to possess him. 

He slid in easily, having not yet swelled to his full size, and the other greedily ate him up. He had to grip his hips and force him still as the other tried to move, his cock beginning to swell and tense slowly. The intrusion quickly became uncomfortable, Lion-O whimpering and beginning to struggle. Fully sheathed and almost completely erect erect Tygra churred sexily, the younger hardly able to appreciate the sound with the burn of his poor over-stretched asshole.

The pain only grew at the other gave a little thrust, Lion-O making a choked sound as the other’s penile spines scraped against his tender walls. His face buried itself into a pillow, biting down into the fabric to try preventing a roar. _Whiskers, it hurt!_ And the burn only seemed to grow worse as the other quickened his pace, thrusting harder and deeper each time. 

His body arched downwards and his legs spread impossibly wide as the soft head of Tygra’s cock pushed against one of his walls deep inside him, a ridiculously obscene sound coming from him as he began to drool all over the pillow.

“ _Th-there!_ ” He managed to demand through his lusty haze, the other’s grip on his hips tightening as his only sign of understanding before he began to pound that spot.

Lion-O was pretty sure he screamed into his pillow in both pain and delight, rocking back into the other like a bitch in heat.

The other growled and Lion-O stifled a roar as teeth bit into the back of his neck, holding him as still as possible as Tygra made shallow thrusts through his orgasm. Lion-O struggled against it, desperate to keep impaling himself on the other.

It took a moment before the other let go, his little brother’s blood on his teeth as he panted. Lion-O whimpered, feeling the other had shrunk inside him and pushing back to try get him deep enough to scratch his maddening itch.

Tygra let out a low churr, dragging his nails through the other’s fur. Slowly, he began to thrust again, relief flooding the other as he slowly swelled back up to his full size.

They mated so many times Tygra lost count, often collapsing with fatigue after he’d spilled, far too hot for comfort. Lion-O however had endless vigour, climbing on top of him and impaling himself with sounds so lewd it must have been taboo.

Tygra could hardly breath as he rocked and bounced on his cock, the other gripping his chest and panting. It was easily the most erotic sight he’d ever been faced with, the image of the other with his fur matted in cum and leaking cock bobbing against his abdomen burning into his brain.

They would nuzzle and rub against one another between rounds, the sun seeming to move faster than usual as it slipped under the horizon and the stars began to shine.

Tygra was the first to pass out, Lion-O finishing himself and spilling on his stomach before collapsing onto the bigger’s chest.

He was vibrating softly under him in his sleep, Lion-O sighing contently as he began to knead the other’s fur and lick at his chest.

In a post mate haze he groomed the other clean, warm seed slipping from his ass as he curled up under his strong arm and fell asleep.

~~s~~

He awoke to an empty bed, naked with the rising sun streaming down on him.

Somewhat coherent he found he had been groomed clean, moving his tongue about as he sat up and noted the stale, unpleasant taste Tygra’s seed had left in his mouth.

A sniff against the air confirmed it had been hours since the other had left, the bed cold where he had slept beside him. The damn shedder had left several orange and white hairs behind, the only clue he had even been in the now ruined sheets.

He supposed they were just... never going to talk about it then. Pretend it never happened. After all, it was probably for the best.

Lion-O flung a pillow at the wall and threw himself back down, curling up with a scowl as he clenched his eyes back shut.

_That asshole._

It still smelt like him, and as much as he hated admitting it the scent was like nip, his body relaxing as the memory of his brother’s churr echoed through his mind.

**Author's Note:**

> Hope you liked! Fun fact, tigers can mate up to 50 times in 24hrs and lions 100 :D


End file.
